\documentclass[10pt]{article}

\usepackage{fullpage}
\usepackage{setspace}
\usepackage{parskip}
\usepackage{titlesec}
\usepackage[section]{placeins}
\usepackage{xcolor}
\usepackage{breakcites}
\usepackage{lineno}
\usepackage{hyphenat}





\PassOptionsToPackage{hyphens}{url}
\usepackage[colorlinks = true,
            linkcolor = blue,
            urlcolor  = blue,
            citecolor = blue,
            anchorcolor = blue]{hyperref}
\usepackage{etoolbox}
\makeatletter
\patchcmd\@combinedblfloats{\box\@outputbox}{\unvbox\@outputbox}{}{%
  \errmessage{\noexpand\@combinedblfloats could not be patched}%
}%
\makeatother


\usepackage{natbib}




\renewenvironment{abstract}
  {{\bfseries\noindent{\abstractname}\par\nobreak}\footnotesize}
  {\bigskip}

\titlespacing{\section}{0pt}{*3}{*1}
\titlespacing{\subsection}{0pt}{*2}{*0.5}
\titlespacing{\subsubsection}{0pt}{*1.5}{0pt}


\usepackage{authblk}


\usepackage{graphicx}
\usepackage[space]{grffile}
\usepackage{latexsym}
\usepackage{textcomp}
\usepackage{longtable}
\usepackage{tabulary}
\usepackage{booktabs,array,multirow}
\usepackage{amsfonts,amsmath,amssymb}
\providecommand\citet{\cite}
\providecommand\citep{\cite}
\providecommand\citealt{\cite}
% You can conditionalize code for latexml or normal latex using this.
\newif\iflatexml\latexmlfalse
\providecommand{\tightlist}{\setlength{\itemsep}{0pt}\setlength{\parskip}{0pt}}%

\AtBeginDocument{\DeclareGraphicsExtensions{.pdf,.PDF,.eps,.EPS,.png,.PNG,.tif,.TIF,.jpg,.JPG,.jpeg,.JPEG}}

\usepackage[utf8]{inputenc}
\usepackage[ngerman,english]{babel}



\usepackage{float}








\begin{document}

\title{Efficacy of Chest X-Rays after Drain Removal in Adult and Paediatric
Patients Undergoing Cardiac and Thoracic Surgery: A Systematic Review}



\author[1]{Myat Thet}%
\author[2]{Khin Phue Phue Han}%
\author[2]{Khun Eaint Hlwar}%
\author[2]{Khaing Soe Thet}%
\author[3]{Aung Oo}%
\affil[1]{Imperial College London}%
\affil[2]{University of Mandalay}%
\affil[3]{Barts Health NHS Trust}%


\vspace{-1em}



  
  \date{May 23, 2024}


\begingroup
\let\center\flushleft
\let\endcenter\endflushleft
\maketitle
\endgroup





\selectlanguage{english}
\begin{abstract}
\textbf{Background:} Chest X-rays are routinely obtained after removal
of chest drains in patients undergoing cardiac and thoracic surgical
procedures. However, a lack of guidelines and evidence could question
the practice. Routine chest X-rays increase exposure to ionising
radiation, increase healthcare costs and lead to overutilisation of
available resources. This review aims to explore the evidence in the
literature regarding the routine use of chest X-rays following the
removal of chest drains. \textbf{Materials \& Method:} A systematic
literature search was conducted in PubMed, Medline via Ovid, Cochrane
central register of control trials (CENTRAL) and ClinicalTrials.gov
without any limit on the publication year. The references of the
included studies are manually screened to identify potentially eligible
studies. \textbf{Results:} A total of 375 studies were retrieved through
the search and 18 studies were included in the review. Incidence of
pneumothorax remains less than 10\% across adult cardiac, and paediatric
cardiac and thoracic surgical populations. The incidence may be as high
as 50\% in adult thoracic surgical patients. However, the
re-intervention rate remains less than 2\% across the populations.
Development of respiratory and cardiovascular symptoms can adequately
guide for a chest X-ray following the drain removal. As an alternative,
bedside ultrasound can be used to detect pneumothorax in the thorax
after the removal of a chest drain without the need for ionising
radiation. \textbf{Conclusion:} A routine chest X-ray following chest
drain removal in adult and paediatric patients undergoing cardiac and
thoracic surgery is not necessary. It can be omitted without
compromising patient safety. Obtaining a chest X-ray should be
clinically guided. Alternatively, bedside ultrasound can be used for the
same purpose without the need for radiation exposure.%
\end{abstract}%



\sloppy


Myat Soe Thet\textsuperscript{1}, Khin Phue Phue Han\textsuperscript{2},
Khun Eaint Hlwar\textsuperscript{2}, Khaing Soe Thet\textsuperscript{2},
Aung Ye Oo\textsuperscript{3}

\textsuperscript{1}Department of Surgery \& Cancer, Faculty of Medicine,
Imperial College London, London, UK

\textsuperscript{2} Mandalay General Hospital, University of Medicine,
Mandalay, Myanmar

\textsuperscript{3}Department of Cardiothoracic Surgery, St
Bartholomew's Hospital, London, UK

\subsection*{Abstract}

{\label{abstract}}

\textbf{Background:} Chest X-rays are routinely obtained after removal
of chest drains in patients undergoing cardiac and thoracic surgical
procedures. However, a lack of guidelines and evidence could question
the practice. Routine chest X-rays increase exposure to ionising
radiation, increase healthcare costs and lead to overutilisation of
available resources. This review aims to explore the evidence in the
literature regarding the routine use of chest X-rays following the
removal of chest drains.

\textbf{Materials \& Method:} A systematic literature search was
conducted in PubMed, Medline via Ovid, Cochrane central register of
control trials (CENTRAL) and ClinicalTrials.gov without any limit on the
publication year. The references of the included studies are manually
screened to identify potentially eligible studies.

\textbf{Results:} A total of 375 studies were retrieved through the
search and 18 studies were included in the review. Incidence of
pneumothorax remains less than 10\% across adult cardiac, and paediatric
cardiac and thoracic surgical populations. The incidence may be as high
as 50\% in adult thoracic surgical patients. However, the
re-intervention rate remains less than 2\% across the populations.
Development of respiratory and cardiovascular symptoms can adequately
guide for a chest X-ray following the drain removal. As an alternative,
bedside ultrasound can be used to detect pneumothorax in the thorax
after the removal of a chest drain without the need for ionising
radiation.

\textbf{Conclusion:} A routine chest X-ray following chest drain removal
in adult and paediatric patients undergoing cardiac and thoracic surgery
is not necessary. It can be omitted without compromising patient safety.
Obtaining a chest X-ray should be clinically guided. Alternatively,
bedside ultrasound can be used for the same purpose without the need for
radiation exposure.

\textbf{Keywords:} Chest X-ray, Chest Drain, Chest Tube, Cardiac
surgery, Thoracic surgery

\section*{INTRODUCTION}

{\label{introduction}}

Chest drains are widely used in cardiothoracic surgery. They are left in
place after surgery for evacuation of air and fluids accumulated in the
thoracic cavities. It has been a standard practice to obtain a routine
chest X-ray once the chest drain is removed. There is no clear guidance
regarding the necessity and timing of the chest X-rays after removal,
yet they are rather empirically obtained.\textsuperscript{1--3}Americal
College of Radiology does not support the routine use of chest X-rays
after the removal of chest drains.\textsuperscript{4}

Undifferentiated routine use of chest X-rays has several disadvantages.
It increases false-positive rates, overall costs and leads to
overutilisation of the healthcare
resources.\textsuperscript{5,6}Furthermore, it increases the exposure to
ironising radiation in patients, especially important in children
because of the cumulative risk of malignancy later in
life.\textsuperscript{3,7}In addition, routine use of chest X-rays does
not influence mortality rate, length of intensive care stay or hospital
stay.\textsuperscript{5}This review aims to explore the evidence in the
literature regarding the routine use of chest X-rays in patients, both
adults and children, undergoing cardiac and thoracic surgical
procedures.

\section*{MATERIALS \& METHODS}

{\label{materials-methods}}

This systematic review follows the 2020 updated Preferred Reporting
Items for Systematic Reviews and Meta-Analyses (PRISMA)
guideline.\textsuperscript{8}

\subsection*{Literature search}

{\label{literature-search}}

We conducted a systematic literature search of studies investigating the
effectiveness of routine chest X-rays after drain removal in patients
undergoing cardiothoracic surgery in Pubmed, Medline via Ovid, Cochrane
central register of control trials (CENTRAL) and ClinicalTrials.gov.
There was no limit on the publication year of the studies, and the last
search was performed on 17 April 2022. The keywords used in combination
with Boolean operators include ``cardiac surgery'', ``thoracic
surgery'', ``cardiothoracic surgery'', ``chest drain removal'', ``chest
tube removal'', ``chest X-ray'' and ``chest radiograph''. The references
of the included studies and relevant reviews are also manually screened
for identifying potentially eligible studies.

\subsection*{Inclusion and exclusion
criteria}

{\label{inclusion-and-exclusion-criteria}}

Original research studies reporting the incidence of pneumothorax and
chest X-ray findings after the chest drain removal in both adult and
paediatric patients undergoing cardiac and thoracic surgery procedures
were included. The exclusion criteria included case reports, case
series, reviews and studies on chest X-rays after drain removal on the
trauma patients exclusively.

\subsection*{Study screening, data extraction and outcome
measures}

{\label{study-screening-data-extraction-and-outcome-measures}}

Two authors (KPPH, KEH) independently reviewed the included studies and
performed data extraction. Disagreements between the authors were
resolved by consensus or by escalating to another author (MST). The
following set of data was extracted: (i) study characteristics including
study design, (ii) patient population characteristics, (iii) incidence
of pneumothorax after removal of drain, (iv) clinical signs and symptoms
following the removal of chest drain, and (v) re-intervention
(re-insertion) of chest drain. The primary outcome measure is the
incidence of pneumothorax, whereas, the secondary outcomes include the
need for re-intervention following the removal of the chest drain, and
signs and symptoms after chest drain removal.

\subsection*{Quality assessment}

{\label{quality-assessment}}

The quality of the included studies was independently assessed by two
authors (KPPH, KST) using the Methodological Index for Nonrandomized
Studies (MINORS).\textsuperscript{9}All included studies are
moderate-quality studies with a global score ranging from 8-12 out of
16.

\section*{RESULTS}

{\label{results}}

A total of 375 studies were retrieved through our search, and 80
duplicates were removed. The titles and abstracts of the remaining 295
studies were screened to identify potentially eligible 22 studies. After
the full-text screening, 18 studies were included in the systematic
review. Eleven studies were conducted in the United States of
America\textsuperscript{1--3,7,10--16}, four studies in the United
Kingdom\textsuperscript{17--20}, one in the
Netherlands\textsuperscript{5}, one in Germany\textsuperscript{21}and
one in Iran\textsuperscript{6}(Table 1). No other studies were
identified through manual screening of references of the included
studies and relevant reviews. PRISMA flow diagram is demonstrated in
Figure 1. Adult patients refer to patients at least 18 years of age, and
paediatric patients refer to patients under the age of 18 in the
studies. Re-intervention is defined as the re-insertion of a chest
drain.

\subsection*{Cardiac surgery adult
patients}

{\label{cardiac-surgery-adult-patients}}

One simple randomised trial\textsuperscript{6}, three prospective cohort
studies\textsuperscript{5,11,19}and one retrospective cohort
study\textsuperscript{18}evaluated the efficacy of routine chest X-rays
constituting a total of 2,080 adult patients undergoing cardiac surgery
procedures, which includes coronary artery bypass grafting (CABG), valve
surgery and atrial septal defect repair, either as isolated procedures
or in combination. The mean duration of chest drain before removal is
1.4-1.8 days\textsuperscript{11,18,19}, and a routine chest X-ray is
obtained within 3-4 hours after the removal.\textsuperscript{6,19}

If a chest X-ray is obtained after the removal, the incidence of
pneumothorax ranges from 1.3-9.3\% with up to 1.3\% of patients
developing respiratory symptoms or haemodynamic changes and
re-intervention was required in 0.5-1.3\% of the
patients.\textsuperscript{5,6,11,18,19}If no routine chest X-ray was
performed after the drain removal, 5.0-11.8\% of the patients developed
respiratory symptoms or haemodynamic changes, of which 0.7-2.5\% would
require re-intervention.\textsuperscript{6,18}

\subsection*{Cardiac surgery paediatric
patients}

{\label{cardiac-surgery-paediatric-patients}}

Two prospective cohort studies\textsuperscript{10,20}and two
retrospective cohort studies\textsuperscript{7,14}have examined the
incidence of pneumothorax and the efficacy of chest X-rays after the
chest drain removal. It includes a total of 12,171 paediatric patients
undergoing congenital cardiac surgery operations. The mean age of the
patients ranges from 0.2-2.7 years. The mean duration of chest drain
varies from 1-6.4 days after the procedure, and a chest X-ray is
performed within 2-6 hours after the removal of the
drain.\textsuperscript{7,10,14,20}

The incidence of pneumothorax after chest drain removal is 0.21\% in a
study with 11,651 patients\textsuperscript{7}and goes as high as 13.6\%
in other studies.\textsuperscript{10,14,20}Clinical symptoms developed
in 0.1-1.87\% of the patients, and 0.1-1.6\% of patients would
eventually undergo re-intervention for the
pneumothorax.\textsuperscript{7,14}

\subsection*{Thoracic surgery adult
patients}

{\label{thoracic-surgery-adult-patients}}

Three prospective studies\textsuperscript{15,17,21}and two retrospective
studies\textsuperscript{1,2}including 921 patients explored the
effectiveness of routine chest X-rays in adult patients undergoing
thoracic surgical procedures, which include both video-assisted
thoracoscopy (VATS) and open surgery. The patients have a mean age of
60-64 years in the studies and had the chest drains for an average
duration ranging from 1-4 days. A chest X-ray is usually performed 2-4
hours after the removal of the chest drain.\textsuperscript{1}

The incidence of pneumothorax on the chest X-ray after removal of the
drain varies greatly from 4 to
48\%.\textsuperscript{1,2,15,17,21}Nonetheless, only up to 0.5\% of
patients need a subsequent intervention after the positive radiographic
findings.\textsuperscript{1,2,17}The incidence of pneumothorax in
asymptomatic patients is approximately 32.8\%, but none of the patients
required re-intervention. They only had clinical observation and
repeated the chest X-rays.\textsuperscript{1}

\subsection*{Thoracic surgery paediatric
patients}

{\label{thoracic-surgery-paediatric-patients}}

Four retrospective studies with a total of 708 paediatric patients
investigated the necessity of performing routine chest X-rays after the
removal of chest drains.\textsuperscript{3,12,13,16}The mean age of
patients in the studies ranges from 7.5 to 9.4 years. The patients
underwent various thoracic surgical procedures including VATS and open
surgeries. The average length of the chest drain is 3.7-7.2 days before
removal, and the chest X-rays are obtained within 2-6 hours after the
removal of the drain.

In the post-drain removal chest X-rays, the incidence of pneumothorax is
3.1-3.9\%\textsuperscript{3,12}with a re-intervention rate is
0.7-1.7\%.\textsuperscript{12,13,16}Clinical symptoms were present in
all patients who required re-intervention. In asymptomatic patients, the
incidence of pneumothorax is 1.8\%\textsuperscript{13}, of which
0.4-0.9\% of the asymptomatic patients would undergo further
re-intervention.\textsuperscript{13,16}

\subsection*{Bedside ultrasound versus chest X-ray after removal of chest
drain}

{\label{bedside-ultrasound-versus-chest-x-ray-after-removal-of-chest-drain}}

There are two prospective observational studies with combined 173
patients, which evaluated the role of bedside ultrasound in comparison
to using chest X-ray after removal of a chest drain to detect
pneumothorax, predominantly in the thoracic adult surgical
population.\textsuperscript{15,21}The overall sensitivity of the bedside
ultrasound is 32\%, however, the sensitivity is increased to 100\% in
detecting pneumothoraces of 3 cm or larger, and the specificity is
85\%.\textsuperscript{21}There is a strong association between
ultrasound and chest X-ray with a therapeutic agreement of
97\%.\textsuperscript{21}There is perfect agreement between the two
methods with a ? statistics value of 1.000.\textsuperscript{15}

\section*{DISCUSSION}

{\label{discussion}}

Studies in the literature recommend that there is no need to routinely
perform a chest X-ray after the removal of a chest drain following
cardiac or thoracic surgery. Diverse patient populations undergoing
different cardiac and thoracic surgeries have demonstrated the incidence
of pneumothorax that requires intervention after removal of chest drain
is low and it is highly correlated with the development of clinical
symptoms. Approximately 1-2\% of patients would require re-intervention
after the chest drain removal, with the exception of the adult thoracic
surgical population, which may be up to 10\% of the patients. The high
incidence could possibly be contributed by the preexisting pulmonary
pathology and complex physiological changes within the pleural space
associated with the thoracic surgical procedures.\textsuperscript{1}

It was previously thought the paediatric population might develop a
higher rate of pneumothorax occurrence since young children are unlikely
to be able to follow breathing commands during the chest drain
removal.\textsuperscript{20}However, it is not the case when a large
study with more than 11,000 paediatric patients in cardiac surgery
demonstrated the incidence of pneumothorax as less than
1\%.\textsuperscript{7}Nevertheless, a good removal technique is
essential to reduce the rate of complications.\textsuperscript{20}

Current literature agrees that performing a chest X-ray is only
necessary if a patient develops respiratory or cardiovascular symptoms
after the removal of the chest drain given that most clinically
significant pneumothorax will eventually develop clinical symptoms.
Omitting a chest X-ray will significantly reduce the healthcare
cost\textsuperscript{1,12,14,18,19}, as well as radiation exposure in
paediatric patients.\textsuperscript{12}Moreover, routine chest X-rays
lead to additional subsequent chest X-rays without the further need for
intervention.\textsuperscript{2,14,18}

On the other hand, a clinically significant pneumothorax might develop
after the removal of the chest drain despite the lack of symptoms.
Especially in very young patients, who are not able to communicate, it
could be concerning that a moderate or large pneumothorax may not
exhibit clinical symptoms in the context of a lack of good respiratory
or cardiovascular physiological reserve, despite very few of them
requiring subsequent intervention.\textsuperscript{7}Assessment of
clinical symptoms solely might not be sufficient, and subgroups of
patients with risk factors should be identified to acquire chest X-rays
following the removal of the chest
drain.\textsuperscript{5,7}Nonetheless, a greater majority of studies
reinforce the fact that routine use of chest X-rays can be eliminated
without compromising patient safety.

An alternative to obtaining a chest X-ray after the removal of a drain
is bedside ultrasound. Despite overall low sensitivity and specificity
compared to X-rays, the bedside ultrasound is highly accurate in
identifying a clinically significant pneumothorax.\textsuperscript{21}It
is safe, has no ionising radiation, has lower cost compared to X-rays,
and has rapid instant interpretation compared to ordering, obtaining and
interpreting a chest X-ray. It is reproducible and requires minimum
experience to detect pneumothorax, with the benefit of detecting further
diagnoses such as pleural effusion and pericardial
effusion.\textsuperscript{15}Yet, the use of ultrasound could be limited
by subjective interpretation of findings depending on the experience of
the operator, postoperative surgical dressings, and anatomical and
physiological changes, especially after thoracic surgery. In spite of
the limitations, an overall low incidence of pneumothorax after chest
drain removal would further favour the use of bedside ultrasound instead
of chest X-rays.

\section*{CONCLUSION}

{\label{conclusion}}

A routine chest X-ray following chest drain removal in adult and
paediatric patients undergoing cardiac and thoracic surgery is not
necessary. It can be omitted without compromising patient safety.
Obtaining chest X-rays should be guided by the development of
respiratory and cardiovascular symptoms. An alternative to the chest
X-ray is to perform a bedside ultrasound, which is rapid, safe,
cost-effective and accurately identifies pneumothorax without ionising
radiation. Further research is required to identify the asymptomatic
patients with a clinically significant pneumothorax, who may need
subsequent intervention.

\section*{REFERENCES}

{\label{references}}

1. Zukowski M, Haas A, Schaefer EW, et al. Are Routine Chest Radiographs
After Chest Tube Removal in Thoracic Surgery Patients Necessary? \emph{J
Surg Res}. 2022;276:160-167. doi:10.1016/j.jss.2022.02.046

2. Porter ED, Fay KA, Hasson RM, Millington TM, Finley DJ, Phillips JD.
Routine Chest X-Rays After Thoracic Surgery Are Unnecessary. \emph{J
Surg Res}. 2020;250:188-192. doi:10.1016/j.jss.2019.12.030

3. Johnson B, Rylander M, Beres AL. Do X-rays after chest tube removal
change patient management? \emph{J Pediatr Surg}. 2017;52(5):813-815.
doi:10.1016/j.jpedsurg.2017.01.047

4. Suh RD, Genshaft SJ, Kirsch J, et al. ACR Appropriateness Criteria\selectlanguage{ngerman}®
Intensive Care Unit Patients. \emph{J Thorac Imaging}.
2015;30(6):W63-W65. doi:10.1097/RTI.0000000000000174

5. Tolsma M, Kröner A, van den Hombergh CL, et al. The clinical value of
routine chest radiographs in the first 24 hours after cardiac surgery.
\emph{Anesth Analg}. 2011;112(1):139-142.
doi:10.1213/ANE.0b013e3181fdf6b7

6. Mandegar M, Shafa M, Ghazinoor M. Efficacy of routine chest X-ray
after chest tube removal in patients undergoing cardiac surgeries.
2007;7(4):686\selectlanguage{english}-689.

7. LaGrasta C, McLellan M, Connor J. Clinical descriptors of
pneumothorax following chest tube removal in paediatric cardiac surgery.
\emph{Cardiol Young}. 2021;31(1):121-124. doi:10.1017/S1047951120003467

8. Page MJ, McKenzie JE, Bossuyt PM, et al. The PRISMA 2020 statement:
an updated guideline for reporting systematic reviews. \emph{BMJ}.
Published online March 29, 2021:n71. doi:10.1136/bmj.n71

9. Slim K, Nini E, Forestier D, Kwiatkowski F, Panis Y, Chipponi J.
Methodological index for non-randomized studies ( \emph{MINORS} ):
development and validation of a new instrument: Methodological index for
non-randomized studies.\emph{ANZ J Surg}. 2003;73(9):712-716.
doi:10.1046/j.1445-2197.2003.02748.x

10. Woodward CS, Dowling D, Taylor RP, Savin C. The routine use of chest
radiographs after chest tube removal in children who have had cardiac
surgery.\emph{J Pediatr Health Care}. 2013;27(3):189-194.
doi:10.1016/j.pedhc.2011.09.003

11. Eisenberg RL, Khabbaz KR. Are chest radiographs routinely indicated
after chest tube removal following cardiac surgery? \emph{AJR Am J
Roentgenol}. 2011;197(1):122-124. doi:10.2214/AJR.10.5856

12. McGrath E, Ranstrom L, Lajoie D, McGlynn L, Mooney D. Is a Chest
Radiograph Required After Removal of Chest Tubes in Children? \emph{J
Pediatr Health Care}. 2017;31(5):588-593.
doi:10.1016/j.pedhc.2017.04.014

13. Kanamori LM, Guner Y, Gibbs D, Schomberg J. Are routine chest X-rays
following chest tube removal necessary in asymptomatic pediatric
patients? \emph{Pediatr Surg Int}. 2021;37(5):631-637.
doi:10.1007/s00383-020-04809-7

14. Pacharn P, Heller DN, Kammen BF, et al. Are chest radiographs
routinely necessary following thoracostomy tube removal? \emph{Pediatr
Radiol}. 2002;32(2):138-142. doi:10.1007/s00247-001-0591-5

15. Saucier S, Motyka C, Killu K. Ultrasonography versus chest
radiography after chest tube removal for the detection of pneumothorax.
\emph{AACN Adv Crit Care}. 2010;21(1):34-38.
doi:10.1097/NCI.0b013e3181c8013a

16. Cunningham JP, Knott EM, Gasior AC, et al. Is routine chest
radiograph necessary after chest tube removal? \emph{J Pediatr Surg}.
2014;49(10):1493-1495. doi:10.1016/j.jpedsurg.2014.01.004

17. Whitehouse MR, Patel A, Morgan JA. The necessity of routine
post-thoracostomy tube chest radiographs in post-operative thoracic
surgery patients.\emph{Surgeon}. 2009;7(2):79-81.
doi:10.1016/s1479-666x(09)80020-6

18. McCormick JT, O'Mara MS, Papasavas PK, Caushaj PF. The use of
routine chest X-ray films after chest tube removal in postoperative
cardiac patients.\emph{Ann Thorac Surg}. 2002;74(6):2161-2164.
doi:10.1016/s0003-4975(02)03982-6

19. Khan T, Chawla G, Daniel R, Swamy M, Dimitri WR. Is routine chest
X-ray following mediastinal drain removal after cardiac surgery useful?
\emph{Eur J Cardiothorac Surg}. 2008;34(3):542-544.
doi:10.1016/j.ejcts.2008.05.002

20. Stather P, Cheshire H, Bogwandas H, Peek G. Pneumothorax post
paediatric chest drain removal. \emph{Thorac Cardiovasc Surg}.
2011;59(5):302-304. doi:10.1055/s-0030-1250357

21. Galetin T, Defosse J, Schieren M, et al. Sensitivity of chest
ultrasound for postoperative pneumothorax in comparison to chest X-ray
after lung resecting surgery.\emph{Eur J Cardiothorac Surg}.
2020;57(5):846-853. doi:10.1093/ejcts/ezz332

\section*{TABLES}

{\label{tables}}

Table 1: Study characteristics included in the systematic review\selectlanguage{english}
\begin{longtable}[]{@{}llllll@{}}
\toprule
Author & Year & Study design & Patient population & Number of patients &
Country\tabularnewline
\midrule
\endhead
Pacharn et al & 2001 & Retrospective cohort & Cardiac surgery,
paediatirc & 374 & United States\tabularnewline
McCormick et al & 2002 & Retrospecrtive cohort & Cardiac surgery, adult
& 1,000 & United Kingdom\tabularnewline
Mandegar et al & 2007 & Randomised controlled trial & Cardiac surgery,
adult & 315 & Iran\tabularnewline
Khan et al & 2008 & Prospective cohort & Cardiac surgery, adult & 151 &
United Kingdom\tabularnewline
Whitehouse et al & 2009 & Prospectice cohort & Thoracic surgery, adult &
74 & United Kingdom\tabularnewline
Stather et al & 2010 & Prospective cohort & Cardiac and thoracic
surgery, paediatric & 93 & United Kingdom\tabularnewline
Saucier et al & 2010 & Case control & Thoracic surgery, adult & 50 &
United States\tabularnewline
Eisenberg et al & 2010 & Prospective cohort & Cardiac surgery, adult &
400 & United States\tabularnewline
Tolsma et al & 2011 & Prospective cohort & Cardiac surgery, adult & 214
& The Netherlands\tabularnewline
Woodward et al & 2011 & Prospective cohort & Cardiac surgery, paediatirc
& 53 & United States\tabularnewline
Cunningham et al & 2014 & Retrospective cohort & Thoracic surgery,
paediatric & 146 & United States\tabularnewline
Johnson et al & 2017 & Retrospectice cohort & Thoracic surgery,
paediatric & 179 & United States\tabularnewline
McGrath et al & 2017 & Retrospective cohort & Thoracic surgery,
paediatric & 281 & United States\tabularnewline
Galetin et al & 2019 & Prospective cohort & Thoracic surgery, adult &
123 & Germany\tabularnewline
Porter et al & 2019 & Retrospective cohort & Thoracic surgery, adult &
241 & United States\tabularnewline
LaGrasta et al & 2020 & Retrospective cohort & Cardiac surgery,
paediatric & 11,651 & United States\tabularnewline
Kanamori et al & 2021 & Retrospective cohort & Thoracic surgery,
paediatric & 102 & United States\tabularnewline
Zukowski et al & 2022 & Retrospective cohort & Thoracic surgery, adult &
433 & United States\tabularnewline
\bottomrule
\end{longtable}

\section*{FIGURES}

{\label{figures}}\selectlanguage{english}
\begin{figure}[H]
\begin{center}
\includegraphics[width=0.70\columnwidth]{figures/image1/image1}

\end{center}
\end{figure}

Figure 1: Preferred Reporting Items for Systematic Reviews and
Meta-Analyses (PRISMA) Flow Diagram

\selectlanguage{english}
\FloatBarrier
\end{document}

